The present disclosure relates to an electronic unit, an optical disk unit, a display unit, and an image pickup unit each of which includes a protective film.
In recent years, various kinds of laser diode devices (semiconductor light-emitting devices) have been widely used as light sources for optical disk recording and reproduction units. Recently, as light sources for next-generation high-density optical disks with high recording density, demand for blue-violet laser diode devices using a Group III-V nitride semiconductor such as gallium nitride (GaN) has been increased.
A protective film made of an oxide is formed on a resonator end surface of each of these laser diode devices to prevent entry of water from outside and to prevent deterioration of and damage to the laser diode devices. For such a protective film, SiO2, SiN, AlO, AlN, and the like are used (for example, refer to Japanese Unexamined Patent Application Publication Nos. 2011-060932, 2007-324193, 2003-332032, 2006-041403, and 2007-189097).